Genesis 27:19Jacob said to his father, "I am Esau, your firstborn. I have done as you told me. Please sit up and eat some of my game, so that you may bless me."

Genesis 27:33Isaac began to tremble violently and said, "Who was it, then, who hunted the game and brought it to me? Before you came in, I ate it all and blessed him--and indeed, he will be blessed!"

Jeremiah 9:4"Let everyone guard against his neighbor; do not trust any brother, for every brother deals craftily, and every friend spreads slander.

Treasury of Scripture

And he said, Your brother came with subtlety, and has taken away your blessing.

Genesis 27:19-23 And Jacob said unto his father, I am Esau thy firstborn; I have done according as thou badest me: arise, I pray thee, sit and eat of my venison, that thy soul may bless me…

2 Kings 10:19 Now therefore call unto me all the prophets of Baal, all his servants, and all his priests; let none be wanting: for I have a great sacrifice to do to Baal; whosoever shall be wanting, he shall not live. But Jehu did it in subtilty, to the intent that he might destroy the worshippers of Baal.

Job 13:7 Will ye speak wickedly for God? and talk deceitfully for him?

Verse 35. - And he (i.e. Isaac) said, Thy brother came with subtlety, - with wisdom (Onkelos); rather with fraud, μετά δόλου (LXX.) - and hath taken away thy blessing - i.e. the blessing which I thought was thine, since Isaac now understood that from the first it had been designed for Jacob.

27:30-40 When Esau understood that Jacob had got the blessing, he cried with a great and exceeding bitter cry. The day is coming, when those that now make light of the blessings of the covenant, and sell their title to spiritual blessings for that which is of no value, will, in vain, ask urgently for them. Isaac, when made sensible of the deceit practised on him, trembled exceedingly. Those who follow the choice of their own affections, rather than the Divine will, get themselves into perplexity. But he soon recovers, and confirms the blessing he had given to Jacob, saying, I have blessed him, and he shall be blessed. Those who part with their wisdom and grace, their faith and a good conscience, for the honours, wealth, or pleasures of this world, however they feign a zeal for the blessing, have judged themselves unworthy of it, and their doom shall be accordingly. A common blessing was bestowed upon Esau. This he desired. Faint desires of happiness, without right choice of the end, and right use of the means, deceive many unto their own ruin. Multitudes go to hell with their mouths full of good wishes. The great difference is, that there is nothing in Esau's blessing which points at Christ; and without that, the fatness of the earth, and the plunder of the field, will stand in little stead. Thus Isaac, by faith, blessed both his sons, according as their lot should be.